A daily multivitamin appears to do little to prevent infections in people 65 and over.

Older people are more likely to be deficient in vitamins and minerals. Lower nutrient levels can affect the immune system and make it harder to fight off infection.

Thus, it makes sense that a low-cost daily vitamin may help boost nutrient levels and help prevent infections.

But in a study by researchers at Aberdeen University in Scotland - reported in the August edition of theBritish Medical Journal -- a daily multivitamin did not help fend off infections in elderly people.

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Vitamins for a Year

The researchers studied 910 men and women aged 65 or older who did not take vitamins or minerals. Participants all lived at home. They were placed on either a daily multivitamin and multimineral supplement or a placebo for one year.

Participants completed daily diaries noting any infections as well as any visits to doctors for infections. They also completed a quality-of-life questionnaire.

They were cautioned to avoid vitamins or minerals from other sources during the trial.

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Little Effect Seen

The participants who took the multivitamin did not report fewer infections than the placebo group.

There was also no difference in antibiotic prescriptions or hospital admissions.

In addition, quality of life was similar between the two groups.

The researchers write that it's possible that the vitamin doses provided in the study were inadequate to affect the immune system.

But at this point there is little evidence to suggest that a daily multivitamin helps boost the immune system and prevent infection in elderly people living at home.

Whether vitamin supplements would help other elderly people, such as those in nursing homes, is not known.

By Patti Connor, reviewed by Michael W. Smith, MD

SOURCE: Avenell, A. British Medical Journal, Aug. 6, 2005; vol 331: pp 324-327.